Hi @Anshu kumar,
Thank you for your patience to help me.
I solved the problem, but I didn't do anything. It is amazing when I opened the Enpass on my iPhone and tried to turn off the sync from iCloud by your way, I got the response below:
It works today!
I think there were something wrong with my iOS network yesterday. Maybe the vpn caused it or maybe not. The iCloud works good in China.
Sincerely, Thank you for your help and the Enpass team, I really like Enpass very mush.